.box {
  display: flex;
  height:800px;
  //justify-content: space-between;
  flex-flow: row;
  border:2px #FF0000 solid;
}
.box-left{
  flex-basis:30%;
  border:2px #00FF00 solid;
}
.box-remain{
  //flex-basis:30%;
  border:2px #0000FF solid;
}


